Remove the extra print statements if you are happy it works as expected. 
use strict;
use warnings;

## add this
use DateTime::Format::Strptime qw(strptime);
my $NOW = DateTime->now();
my $MAX_AGE = 60;
print "Time now is $NOW\n";
##

my %users;
my %conn;

while (<DATA>) { # I use DATA handle instead of $fh for convenience
 if( /\bBIND\b/ ) {
  my( $conn, $uid ) = /conn=(\d+).*uid=(.*?),/;
    $conn{$conn} = $uid;
  }
  if( /SRCH=Q/ ) {
    my ($timestamp, $conn) = /\[(.*?)\] conn=(\d+)/;
    
    ## add this
    my $dt = strptime('%d/%B/%Y:%T',substr($timestamp,0,20));
    my $age = $dt->delta_ms( $NOW )->in_units('minutes');
    print $timestamp." = " .$dt->datetime." ; $age mins\n";
    ##
    
    ## add condition
    if ($age >= $MAX_AGE){
      my $uid = $conn{$conn}; 
      ++$users{$uid};
    }
  }
}


for my $uid (keys %users) {
  my $count = $users{$uid};
  print "\t=> Bad user $uid ! count = $count\n" if  $count > 3;
}

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poj

In reply to Re^5: Undefined Error by poj
in thread Undefined Error by johnrein55

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